Hydrocarbons and other fluids are often contained within subterranean formations at elevated pressures. Wells drilled into these formations allow the elevated pressure within the formation to force the fluids to the surface. However, in low pressure formations, or when formation pressure has diminished, the formation pressure may be insufficient to force fluids to the surface. In these cases, a positive displacement pump, such as a piston pump, can be installed to provide the required pressure to produce the fluids.
The function of pumping systems in gas wells is to produce liquid, generally water, that enters the well bore naturally with the gas. This is generally necessary only on low flow rate gas wells. In high flow rate gas wells, the velocity of the gas tends to be sufficient enough that it carries the water to the surface. In low flow rate wells, the water accumulates in the well bore and restricts the flow of gas. By pumping out the water, the pump allows the well to flow at a higher gas rate, and this additional produced gas, which eventually is related to additional revenue, and helps pay for the pumping unit.